1. Field Of The Invention
The present invention relates to a locking clip and in particular to a locking clip to be used as a replacement for at least a pair of contacts in a conventional low insertion force edge board connector to hold a circuit board in the connector without affecting the low wear characteristics thereof.
2. The Prior Art
There are many instances when it is desirable to have a low insertion force connector for making engagement with the edge of the printed circuit board. The primary reason for having such a connector is to protect the pads on the circit board from excessive wear. This is generally accomplished by one of several means including camming the housing apart and/or camming the contacts apart to allow insertion of the board between spaced rows of contacts without the contacts dragging across the pads. Examples of such connectors can be found in U.S. Pat. Nos. 3,594,699 and 3,710,303. While the connectors such as those described in the above mentioned patents do accomplish the goal of reducing wear on the pads of a printed circit board, they do not always sufficiently secure the board in the connector to prevent unintentional disengagement thereof. An example of such incidences would be an apparatus which would be subjected to excessive or high amounts of vibration. The connectors described in the above mentioned patents do serve to lock the board in place but the connectors themselves are rather complex and expensive to produce. Also, since there are a great number of moving parts, there is always the problem of potential jamming or wear of the parts which would reduce the efficiency thereof.
Attempts have been made to provide a type of locking clip which could be used to secure a circuit board in a housing. Examples of this type of clip can be found in U.S. Pat. Nos. 3,278,714, and 3,439,227. Both of the clips disclosed in these patents have the disadvantage that they are not suitable for replacing contacts in an existing housing but must be used with a particular type of housing and a particular type of printed circuit board.
Other known contacts have been proposed which will serve in cooperation with a camming device in an edge board connector to lockingly secure a circit board in a connector. Both of these contacts have portions which engage through holes in the circuit board thereby electrically and mechanically locking the board in the connector.
U.S. Pat. Nos. 3,207,536 and 3,368,182 both disclose axially operated coupling devices which are inserted into connector housings. The relative movement of the housing members with respect to one another accomplishes the locking by the axial movement of the coupling devices. Here again the device described is quite similar to the previously discussed prior art since cooperation between the connector members is necessary in order to effect the desired operation.
All of the above discussed prior art devices have the prime disadvantage in that they are useful only with a single type of connector and this connector is generally relatively expensive to produce since it involves a multiplicity of parts.